This project studies several types of instrumentation to understand basic aspects of their operation with an eye to optimizing their operation. A major component of this research related to the resolution of peaks in both gel electrophoresis and capillary zone electrophoresis. Standard theories of electrophoresis lead to a definition of resolution that predicts that it always increase as the measurement time increases. Instrumentation has recently become available to measure different features of peak shape in electrophoresis. This has been used to demonstrate that the commonly assumed shapes do not always agree with experiment. A non-Markovian theory developed fifteen years ago yields results that differ from those associated with the standard theory, and was shown to yield results agreeing with experiment. Another aspect of this continuing project relates to the development of measures of resolution differing from those in commonly used. All of these projects were carried out in collaboration with chemists in the laboratory of Dr. A. Chrambach (NICHD). A second project relates to the optimization of experiments designed to measure spin-spin relaxation times in NMR. Simply expressed rules for optimizing such experiments have indicated the possibility of improving the precision obtainable from a fixed number of measurement times by as much as 75%. This work was carried out together with Dr. R.G.S. Spencer (NIA). Dr. Sinisa Pajevic has been collaborating with Drs. P. Basser (NCRR) and C. Pierpaoli (NINDS) on the improvement of diffusion tensor imaging. By using the appropriate color representations of the measured mathematical parameters they were able to enhance the distinction between different anatomical features as determined by several radiologists. Work on different aspects of this problem, i.e., the representation and segmentation of images obtained with this modality is continuing. Drs. Pajevic and Weiss continue to work with Dr. A. Ling (CC) on a comparison of different lossy compression schemes presently applied to CAT scan data obtained from different organs. Thus far they have initiated a study of wavelet transformed based compression, and have gotten six radiologists to participate in a test to determine a level of tolerable compression. Further radiologists are presently being sought.